Aquarium



FIG. 1 is a top plan view of an aquarium embodying my new design;

FIG. 2 is a front elevational view;

FIG. 3 is a bottom plan view;

FIG. 4 is a rear elevational view;

FIG. 5 is a left end elevational view;

FIG. 6 is a right end elevational view; and

FIG. 7 is a perspective view thereof with the lid in a raised position. 

The ornamental design for an aquarium, substantially as shown and described. 